Turbo Duo with memory save issue (finally solved)

[bust3dstr8]

If that's a genuine NEC cap, I'll eat my hat.  :-"

[NightWolve]

Hmmm, you did make me do a double-take and now I see that they're marked as "used" - didn't catch that before which would explain the pricing. So he's got 30 5-packs left and they're of "used" quality... Where did they come from then I wonder ? Still haven't received my order, will update when it gets here... Just never heard of "used" caps being sold before, that caught me by surprise!

http://www.ebay.com/itm/Technical-Durable-5-Pcs-1F-Farad-Capacitor-Supercapacitor-NEC-TOKIN-5-5V-HCCA-/231397405230?pt=LH_DefaultDomain_2&hash=item35e05c322e

So here's another listing. The seller is claiming "new other" for it.

A new, unused item with absolutely no signs of wear. The item may be missing the original packaging, or in the original packaging but not sealed. The item may be a factory second or a new, unused item with defects. See the seller’s listing for full details and description of any imperfections.

If these caps have never been soldered on to something, then maybe they're trying to say they're used-looking or something. I hope at least that's what's going on here.

[bust3dstr8]

Ah...I didn't see the used, but that makes sense too. I figured it was a Chinese knockoff, no way it could of been 5 New NEC caps at that price.

Nightwolve....you may want to read into Chinese electronic salvage a bit  they're pretty f*cking shady.

Here is a story from fairly recently. I may not be exact, but it was pretty much along these lines.

A arcade dealer bought 1000 hard to find 2.5A MOSFETS from a Chinese vender. After numberous failures he cracked one open and looked at the die. He then cracked open the much more common 1.5A version of the MOSFET and found it had the same die.

Those f*ckers where blasting the cheapos and then rescreening them with the rarer MOSFET numbers and selling them as such.

[thesteve]

thats a common counterfeiting process
your best option is to learn how to sub the parts with more common ones

[NightWolve]

Yeah, I'm a little nervous now with that order, but it was only ~$2 and so far I haven't had a problem with any Chinese sellers I bought parts from - this one has a ~98% positive rating. Gonna check the legs as soon as I get them and see if they were soldered on to something... That's weird though, selling "used" caps, I totally missed that shit somehow. I would take just ONE new one at $2-3 bucks and be done with it, I won't need those extras anyway. Anyhow, I'll let you guys know when I get my order what the deal is. Should be here this week.

[SegaSonic91]

Hmm, very interesting.  Adding life to the DUOs backup life span would be fantastic.  I've lost so many saves on my original RX from 2004.  I hate the DUOs backup RAM solution.  A battery would have been so much better!

I will be waiting for the report once they arrive. 

[NightWolve]

Le Steve offered a diode with lithium battery mod/solution if you'd like.

You need:

1) CR3032 Lithium battery holder for 2 batteries
2) 2 CR3032 Lithium coin cell batteries
3) 2 standard diodes

CR3032 batteries are 3 Volts each, so together they would be 6 Volts. The positive/+ side would connect to 2 diodes facing outward which would connect the + tap on the motherboard, negative of the holder to the negative/ground of the motherboard, easy enough (where the super capacitor is now!).

The 2 diodes give you a slight voltage drop so the batteries provide 5 Volts afterwards, and the diodes' one-way direction prevents 5 Volts going back towards the batteries when the system is turned on which would cause a recharge situation, and hence damage.

Unless you wanna buy those $11 rechargeable lithium batteries though that come in the CR3032 size, this is one route. A rechargeable would make it easier.

[bust3dstr8]

Someone needs to try a FeRam in the Duo.

[Brraap]

I missed that too NightWolve, hmmm...we might be getting Chinese scraps 

[NightWolve]

Yeah, sorry about that. It was unexpected for caps (that idea of used ones being sold) and my eyes just went passed that detail.

[Bernie]

Le Steve offered a diode with lithium battery mod/solution if you'd like.

You need:

1) CR3032 Lithium battery holder for 2 batteries
2) 2 CR3032 Lithium coin cell batteries
3) 2 standard diodes

CR3032 batteries are 3 Volts each, so together they would be 6 Volts. The positive/+ side would connect to 2 diodes facing outward which would connect the + tap on the motherboard, negative of the holder to the negative/ground of the motherboard, easy enough (where the super capacitor is now!).

The 2 diodes give you a slight voltage drop so the batteries provide 5 Volts afterwards, and the diodes' one-way direction prevents 5 Volts going back towards the batteries when the system is turned on which would cause a recharge situation, and hence damage.

Unless you wanna buy those $11 rechargeable lithium batteries though that come in the CR3032 size, this is one route. A rechargeable would make it easier.

Wait...what??  Steve is currently offering this mod?  That sounds awesome!

[NightWolve]

That is one of his ideas so in theory the save state should last as long as say a SNES cart with those batteries. He hasn't done it for anybody, I had just asked him if you could convert it to battery style. I would trust the rechargeable ones more though cause diodes aren't 100% at one-way electron flow control but I guess 2 are good enough since that's how it probably is right now for all carts with regular lithium batteries soldered on. I did notice my Zelda cart still had a save stored so they can last well over 15 years.

[Brraap]

Im sure even if they are used, at least 1 of them should work, if not, it was only a few $ 

[NightWolve]

OK guys, really bad news... I got scammed - he's a scammer... The epic failure here was the decision to use iron/steel instead of aluminum for the metal body of the capacitor. These are not just used, they're badly corroded/rusted from sitting around too long as well, possibly in a very high humidity environment... This is a bit of debacle - I wouldn't use any of these... I'm gonna leave the f--ker a negative review... He should've used a screenshot like I'm posting below to tell the truth as to exactly what condition they're in, how "used" is used, etc...

Damn bastard, look at this shit, like they've been sitting in salt water for ages:

http://i237.photobucket.com/albums/ff216/Sephiroth1975/Tech/IMG_20150204_133010.jpg


http://i237.photobucket.com/albums/ff216/Sephiroth1975/Tech/IMG_20150204_132707.jpg


F--k am I supposed to do with that when you couldn't in good conscience trust ANY of them ? The top end of the steel body at parts is corroded/rusted inward (AKA eaten away!) so they're surely headed for leaks... He seriously expected possible reuse for these ? I haven't tested them as I don't care if they work, they're not trustworthy by appearance alone!

Compare to the photos he's using to sell these ??

http://www.ebay.com/itm/High-Light-5-Pcs-1F-Farad-Capacitor-Supercapacitor-NEC-TOKIN-5-5V-HGCA-/191443047755?pt=LH_DefaultDomain_2&hash=item2c92e5154b

He's a f--king scammer!! He told you they're "used" but compare the "marketing" photos he used to what I got in the f--king mail!!!

[bust3dstr8]

Look on the bright side...at least there wasn't a severed child finger in there as well 



















.....but ya, sorry to see you got boned.  Chinese salvage people are all underhanded a$$holes for the most part.